This is part of the hard limitation of Windows 8 Store Apps that only 1 can be running full screen at a time. 2 if one is snapped. This was done to limit the performance hit that running multiple apps would have on tablets and ultrabooks.

This is part of the hard limitation of Windows 8 Store Apps that only 1 can be running full screen at a time. 2 if one is snapped. This was done to limit the performance hit that running multiple apps would have on tablets and ultrabooks.

This is definitely true. I also have a feeling that they did some research into how many people really have multiple monitors. It probably wasn't worth the development time to get it to work in this manor. It will probably come in a service pack.

To be honest, I thought the same way at first. I'm actually very happy with the way it works currently. That isn't to say I'd love to be able to run more than 2. I normally always browse with a full screen browser, so it works perfectly for me. I have my email/music/other metro enabled apps on my left monitor, and my browser (IE) on the main display.

There's a lot to like about Metro but the overall implementation is pretty poor, especially when talking about multi-monitor support and the use of large, high resolution displays. Most apps dom't take advantage of the vertical resolution on high resolution displays; you can't have apps running on multiple monitors; dragging an app from one screen to another automatically snaps it; you can't use the same gestures as desktop apps (drag to top to maximise, for instance); there is no proper shared task manager for both environments (there is alt-tab, though that's not designed for tablets and is a feature most users don't know about); apps don't auto-update or don't do so promptly (to get updates I have to go into Store and manually trigger them, despite auto-updates being enabled); you can't move multiple apps on the Start Screen (aside from moving groups); the Charm bar is horrible, especially with multiple monitors.

I do use Metro apps but only those with worthwhile functionality, like XE.com, Solitaire and Cocktail Flow. That said, there's no reason most of my main criticisms couldn't be addressed with Windows 9.

This is definitely true. I also have a feeling that they did some research into how many people really have multiple monitors. It probably wasn't worth the development time to get it to work in this manor. It will probably come in a service pack.

This is what it's all about IMO. It has nothing to do with whether the Metro UI is a tablet UI, it's just that multi-monitor users are a niche that are more likely to run desktop apps than simple Metro apps.